Coronavirus disease 2019 (COVID-19) is a viral respiratory disease that spreads rapidly, reaching pandemic status, causing the collapse of numerous health systems, and a strong economic and social ...impact. The treatment so far has not been well established and there are several clinical trials testing known drugs that have antiviral activity, due to the urgency that the global situation imposes. Drugs with specific mechanisms of action can take years to be discovered, while vaccines may also take a long time to be widely distributed while new virus variants emerge. Thus, drug repositioning has been shown to be a good strategy for defining new therapeutic approaches. Studies of the effect of enriched heparin in the replication of severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) in vitro assays justify the advance for clinical tests.
A phase I/II triple-blind parallel clinical trial will be conducted. Fifty participants with radiological diagnosis of grade IIA pneumonia will be selected, which will be allocated in 2 arms. Participants allocated in Group 1 (placebo) will receive nebulized 0.9% saline. Participants allocated in Group 2 (intervention) will receive nebulized enriched heparin (2.5 mg/mL 0.9% saline). Both groups will receive the respective solutions on a 4/4 hour basis, for 7 days. The main outcomes of interest will be safety (absence of serious adverse events) and efficacy (measured by the viral load).Protocols will be filled on a daily basis, ranging from day 0 (diagnosis) until day 8.
Amphibians are probably the most vulnerable group to climate change and climate-change associate diseases. This ongoing biodiversity crisis makes it thus imperative to improve the taxonomy of anurans ...in biodiverse but understudied areas such as Amazonia. In this study, we applied robust integrative taxonomic methods combining genetic (mitochondrial 16S, 12S and COI genes), morphological and environmental data to delimit species of the genus
(Anura: Bufonidae) sampled from throughout their pan-Amazonian distribution. Our study confirms the hypothesis that the species diversity of the genus is grossly underestimated. Our analyses suggest the existence of eighteen linages of which seven are nominal species, three Deep Conspecific Lineages, one Unconfirmed Candidate Species, three Uncategorized Lineages, and four Confirmed Candidate Species and described herein. We also propose a phylogenetic hypothesis for the genus and discuss its implications for historical biogeography of this Amazonian group.
Abstract
The outstanding biodiversity of the Guiana Shield has raised many questions about its origins and evolution. Frogs of the genera Adelastes, Otophryne and Synapturanus form an ancient lineage ...distributed mostly across this region. These genera display strikingly disparate morphologies and life-history traits. Notably, Synapturanus is conspicuously adapted to fossoriality and is the only genus within this group to have dispersed further into Amazonia. Moreover, morphological differences among Synapturanus species suggest different degrees of fossoriality that might be linked to their biogeographical history. Through integrative analysis of genetic, morphometric and acoustic data, we delimited 25 species in this clade, representing a fourfold increase. We found that the entire clade started to diversify ~55 Mya and Synapturanus ~30 Mya. Members of this genus probably dispersed three times out of the Guiana Shield both before and after the Pebas system, a wetland ecosystem occupying most of Western Amazonia during the Miocene. Using a three-dimensional osteological dataset, we characterized a high morphological disparity across the three genera. Within Synapturanus, we further characterized distinct phenotypes that emerged concomitantly with dispersals during the Miocene and possibly represent adaptations to different habitats, such as soils with different physical properties.
The Amazonian red side-necked turtle
is an endemic Amazonian Chelidae species that occurs in small streams throughout Colombia and Brazil river basins. Little is known about various biological ...aspects of this species, including its sex determination strategies. Among chelids, the greatest karyotype diversity is found in the Neotropical species, with several 2
configurations, including cases of triploidy. Here, we investigate the karyotype of
by applying combined conventional and molecular cytogenetic procedures. This allowed us to discover a genetic sex-determining mechanism that shares an ancestral micro XY sex chromosome system. This ancient micro XY system recruited distinct repeat motifs before it diverged from several South America and Australasian species. We propose that such a system dates back to the earliest lineages of the chelid species before the split of South America and Australasian lineages.
Anurans in the Rhinella margaritifera group have a long history of taxonomic confusion, mainly by morphological similarity between species and lack of acoustic and genetic data for many of the 19 ...described species. Herein, we presented data for Rhinella gildae based on recently collected specimens from its type locality. We provide patterns of morphological variation, measurements, advertisement and release calls and infer the phylogenetic position of R. gildae. The species geographical distribution was updated, occurring in two Amazonian localities in Maranhão state, and Cerrado areas in Maranhão and Tocantins states and also in a rainforest enclave inside Caatinga domain in Ceará state.
Turtles are one of the most threatened groups of vertebrates, with about 60% of species classified at some level of extinction risk. Compounding this extinction crisis are cryptic species and species ...complexes that are evaluated under a single species epithet but harbor multiple species, each of which needs to be evaluated independently. The Phrynops geoffroanus species group is a classic example. Described first in 1812, it is currently thought to harbor multiple species. To test this hypothesis, we collected mitochondrial and nuclear genomic data, morphometric data, and distribution and associated biome information. We applied statistically rigorous species delimitation analyses, taxonomic hypotheses tests, and fully coalescent phylogenetic reconstruction methods, concluding that the Phrynops geoffroanus species complex comprises four geographically structured species/lineages that diverged during the Pleistocene and are currently geographically structured along the main South American river basins and biomes. These species/lineages show subtle and largely non-significant differences in shape but are characterized by differences in coloration and patterns of marks on the head and plastron. Our results contribute to the understanding of species diversity and diversification of biodiversity in South America and provide an important basis for the conservation of freshwater turtles.
Boana hobbsi is a poorly known hylid frog currently placed within the Boana punctata group. Yet, morphological, ecological and bioacoustic traits do not support this placement, with no molecular data ...being available to date to test this hypothesis. Based on newly collected mitochondrial DNA sequences, morphological data review and field observations, we provide new insight into the phylogenetic relationships, morphological variations and geographic distribution of B. hobbsi. Our findings reveal that B. hobbsi is nested (with strong support) within the Boana benitezi group, recovering once more a polyphyletic Boana punctata group. Supported by this new genetic, morphological and ecological evidence, we propose a new taxonomic arrangement which includes B. hobbsi as a member of the Boana benitezi group. Furthermore, we emphasize the importance of conducting biological inventories in remote Amazonian areas, where many taxonomic and geographic knowledge gaps persist with regards to Amphibian diversity.
A new species of the genus Amazophrynella (Anura, Bufonidae) is described from the departments of Madre de Dios, Cusco and Junin in Peru. An integrative taxonomy approach is used. A morphological ...diagnosis, morphometrics comparisons, description of the advertisement call, and the phylogenetic relationships of the new species are provided. Amazophrynella javierbustamantei sp. n. differs from other species of Amazophrynella by: intermediate body-size (snout-vent length 14.9 mm in males, n = 26 and 19.6 mm in females, n = 20), tuberculate skin texture of body, greatest hand length of the Amazophrynella spp. (3.6 mm in males, n = 26 and 4.6 mm in females, n = 20), venter coloration yellowish, tiny rounded black points covering the venter, and thirteen molecular autapomorphies in the 16S RNA gene. Its distribution varies from 215 to 708 m a.s.l. This discovery highlights the importance of the remnant forest in preserving the biodiversity in Peru, and increase in seven the species formally described in the genus Amazophrynella.
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